Such a switch is known from the German patent publication DE 10 2008 039 066 A1. This switch comprises a rotor housing and an electric contact arm, rotatably mounted in the rotor housing, the contact arm being pivotable between an on-position and an off-position as well as relative to the rotor housing. In the on-position, the electric contact arm connects a contact element of the contact arm to a stationary contact element of the switch. In the off-position, the contact element of the contact arm and the stationary contact element of the switch are separated. For switching on and off, the contact arm can be pivoted by rotating the rotor housing; the rotating rotor housing carries the contact arm with it and also pivots the contact arm. In addition, the contact arm can pivot even without a rotation of the rotor housing, i.e. relative to the rotor housing, namely if the current flowing via the contact arm becomes too great: in this case, the contact arm is pivoted relative to the rotor by way of a magnetic force induced by the current, the contact element of the contact arm and the stationary contact element of the switch being separated from one another as a result.
In one of the embodiments described in the German patent publication DE 10 2008 039 066 A1, two intermediate parts are present which, in a predefined locking position, lock the pivotable contact arm with the rotor housing and, in the event of a relative rotation between the pivotable contact arm and the rotor housing, are moved away from the predefined locking position. Each of the two intermediate parts consists of a pressure element which is pivotably connected at one end to a pivot bearing of the contact arm and at another end holds a roller via a rotation bearing. The roller can roll on a wall section of the switch.